The remarks came after the allegedly accidental release on Monday of an address to the nation that Mr Temer intended to deliver after a hypothetical congressional vote that would suspend Ms Rousseff from office.

In the 13-minute audio, which Mr Temer said he unintentionally sent to politicians through an instant messenger app, the vice president speaks as if he had already assumed the top job.

Ms Rousseff said she was "shocked" by the recording, which she said "reveals treason against me and against democracy".

The president said: "The mask of the conspirators has fallen."

With 342 votes in the 513-member Chamber of Deputies needed for the process to move forwards, analysts say the outcome is too close to call.

Ms Rousseff took a hit on Tuesday when 31 of the 47 deputies with the Progressive Party, the country's fourth-largest party and a member of her governing coalition, announced they would vote for impeachment.